Israel has decided to reassess its relations with the Palestinian Authority and its chairman, Mahmoud Abbas, due to the unity government agreement reached between Fatah and Hamas in Mecca last week.

The agreement, including its implications for the diplomatic process and Israeli-Palestinian relations, will be at the center of Monday's trilateral summit in Jerusalem, senior government sources said Tuesday.

The summit, to take place at Jerusalem's David Citadel Hotel, will include Prime Minister Ehud Olmert, Palestinian Authority Chairman Mahmoud Abbas and U.S. Secretary of State Condoleezza Rice. Olmert departs on Wednesday for a visit to Turkey, and Rice is due to arrive in the region on Saturday.

At a preparatory meeting on the summit Tuesday, Olmert said that the strategic and geopolitical implications of the Mecca agreement are no less important than those of Hamas's victory in the elections for the Palestinian Legislative Council a year ago. He added that Israel must calculate its policies toward the new Palestinian unity government carefully.

"The chances that there will be talk of a political horizon at the summit, given that a Fatah-Hamas government is waiting in the corner, are not high," a well-placed government source said.

Olmert is planning to demand that Abbas obtain the release of abducted Israel Defense Forces soldier Gilad Shalit. "Abu Mazen [Abbas] can no longer evade responsibility for the release of Shalit if he sits with Hamas in the same government," the source explained.

Government sources added that at Monday's summit, Olmert has no intention of offering Abbas any goodwill gestures aimed at easing daily life for Palestinian civilians, such as those that followed the two men's meeting on December 23, 2006.

The Mecca Agreement poses a dilemma for Israel. Before it was signed, Israel maintained contacts with Abbas, who it presented as a moderate, while boycotting the Hamas government. The tripartite summit, which was scheduled during Rice's previous visit to the region, was meant to restart the diplomatic process. But following the Mecca Agreement, the lines distinguishing the moderates from the extremists among the Palestinians have become blurred.

Olmert will therefore seek clarifications from Abbas and Rice on how the relationship with the new Palestinian government will be conducted.

During Tuesday's preparatory meeting, which was also attended by Foreign Minister Tzipi Livni, Defense Minister Amir Peretz and the heads of the intelligence agencies, Olmert expressed his view that Israel does not have to take the lead in moves against the new Palestinian government or in ceasing contacts with Abbas. Instead of Israel positioning itself at the forefront of the struggle, he said, it should conduct a diplomatic campaign to demand that the international community insist on the Palestinians meeting the three conditions put forth by the Quartet: recognizing Israel, relinquishing violence and honoring previous agreements between Israel and the PLO.

Over the last few days, Olmert has talked on the telephone with Rice, United Nations Secretary General Ban Ki-moon and the leaders of Russia, Britain and Germany. According to government sources, this diplomatic effort aims to marshal international pressure on Abbas in order to influence the Palestinian unity government's diplomatic platform.

One of the main recommendations to emerge from Tuesday's meeting was that Israel should avoid doing anything that would cause political harm to Saudi Arabia, which brokered the Mecca Agreement, so as not to undermine Riyadh's position as part of the region's "axis of moderates" against the developing threat from Iran.

At a meeting of the Knesset Foreign Affairs and Defense Committee on Monday, opposition leader Benjamin Netanyahu urged Olmert to cancel the tripartite summit in response to the Mecca Agreement. Olmert's reply was that there is no need to respond rashly. Senior Israeli officials did weigh the possibility of canceling the summit over the weekend, but Rice insisted that the meeting be held.

During his visit to Turkey Wednesday, Olmert will meet with Turkish President Ahmet Sezer and Prime Minister Recep Tayyip Erdogan. He will also meet Foreign Minister Abdullah Gul and Defense Minister Vecdi Gonul.

It is not clear whether the visit, which was originally scheduled to take place Thursday, was moved forward because a secret meeting has been arranged with some Arab or Muslim figure via Turkish mediation, or for some other reason. A year and a half ago, the foreign ministers of Israel and Pakistan held their first public meeting in Istanbul, and the Turkish government has repeatedly offered its services in mediating between Israel and Syria, the Palestinians and others.

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